In an end-stage clinical trial comparing NicOx's painkiller candidate naproxcinod to standard naproxen in 118 patients with controlled hypertension, good safety and tolerability were shown by all naproxcinod doses, the French biotech company NicOx stated.

Naproxcinod is the first investigational drug in the new Cyclooxygenase-Inhibiting Nitric Oxide-Donator (CINOD) class of anti-inflammatory agents, and part of the trial goal was to compare it with existing non-steroidal anti-inflammatory agents (NSAIDs) such as naproxen and ibuprofen – NSAIDs can raise blood pressure, which is a side effect of particular concern among people with osteoarthritis, for whom the painkiller is intended.

In the study, 118 patients were randomized on a 1:1 basis to receive naproxcinod or naproxen, with escalating doses every three weeks. The trial included three doses of naproxcinod (375 mg bid, 750 mg bid and a supra-therapeutic dose of 1125 mg bid), which were compared to naproxen (250, 500 and 750 mg bid).

The primary goal of the study was to characterize the 24-hour arterial blood pressure profile of the three doses of naproxcinod, as measured by FDA validated ABPM device after each dose, compared to naproxen. At all time points, naproxcinod showed a decrease in the mean 24-hour SBP and DBP from baseline in contrast to naproxen, said the company.

In terms of the overall treatment effect, as an average over week 3, 6 and 9, naproxen raised SBP by 1.5 mmHg from baseline, while naproxcinod lowered it by 2.3 mmHg, resulting in a difference between the two treatments of 3.8 mmHg (p < > =0.011) in favor of naproxcinod.

NicOx estimates it will be submitting a New Drug Application (NDA) for naproxcinod with the U.S. Food and Drug Administration (FDA) by mid-2009.